Mail deleting messages after a month

[muvuth]

Hi, all.
I'm desperate here.

Apple Mail keeps deleting my messages after 3-4 weeks from reception, and I can't find the reason.

I had Catalina for a few months, had the same problem at first and then realized it was because I had IMAP accounts. I then changed all accounts to POP, and that solved it.

Now I "downgraded" to Mojave so I had to redo all the settings, and voilà: Mail is deleting my messages again, despite the account being POP.
I have multiple accounts, some with Gmail (including G Suite) and some on a separate server. The Google-based ones are always there, but the other ones get deleted.
Server settings, you might think? I checked, and there's no mention of deleting messages after they are downloaded. In fact, Mail seems to be overriding that, as it deletes messages from the server after that period of time!
In any case, being a POP account, that should make no difference, right?

Also, the same settings worked previously, but now they don't. Same Mac, just changed the OS because Catalina was a pain in the neck.

I'm desperate, if anyone has any clues I'll be sooooo glad to try anything. They're work emails!

Muvuth

 

[Madonepro]

Have you tried in the mail app, preferences/accounts/mailbox behaviours and then check in there.

 

[muvuth]

Hi, thanks for the reply and sorry I haven't checked your response earlier.
Yes, I have. And all the accounts I have, have the same settings.

I'm desperate!

 

[Eliott69]

Your photo in one of your attachment says it:
"Erase deleted messages: After one month"

 

[muvuth]

At first I considered that too, but all other accounts have the same settings there, too. I think that just affect messages you delete, whereas my problem is that messages I want to keep are deleted automatically